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1. (WO1999005709) EXPOSURE METHOD AND ALIGNER

Pub. No.:    WO/1999/005709    International Application No.:    PCT/JP1998/003305
Publication Date: Fri Feb 05 00:59:59 CET 1999 International Filing Date: Sat Jul 25 01:59:59 CEST 1998
IPC: G03F 7/20
Applicants: NIKON CORPORATION

NISHI, Kenji

Inventors: NISHI, Kenji

Title: EXPOSURE METHOD AND ALIGNER
Abstract:
When a mask pattern is transferred by scanning exposure onto a photosensitive wafer by a projection aligner, static image distorsion characteristics in the scanning direction are smoothed over the width of an exposed area and turned to dynamic image distorsioncharacteristics. At least the random component of the dynamic image distorsion characteristics is corrected by placing in the projection optical path an image distorsion correction plate which is prepared by locally polishing the surface of a transparent plate having parallel sides. Considering that other aberrations are also smoothed during the scanning exposure and turned to dynamic aberration characteristics, a correction plate which will minimize other aberrations is manufactured beforehand and mounted in the projection optical path. As a result, aberrations occurring in an illumination optical system in the projection optical system of a projection aligner using ultraviolet illumination light are reduced.